Natural Disaters Homework

My next homework projest can be found on:

http://naturaldisaters4science.blogspot.com/

Thank you.

GM Food Project

I have created a new blog for my GM Food Project.

To fing this blog follow this link
http://geneticallymodifiedfoodscienceproject.blogspot.com/

Thanks
Sophie Jayne Newlove
☺☻☺

Case Sudy - Burgular Murder

There has been a burglary at 7 Trenton Road. It took place on the 14th of November at around 7:30 am. Not only a burglary but a murder.

There was only one witness and they saw a man entering the house at around 7 am with a grey rucksack. We later found that rucksack in the forest out the back of the house. The man was wearing a navy hoodie and a red cap. The witness saw the door open on her way back down the street and immediately called the police. This is how we found the house.
The woman who was murdered was 72 year old Florence Nightingale. The arrangement of the house looked like she was just about to sit down to her lunch. It looks like the knife she was killed with was the knife she was using to cut the bread she was going to eat with her soup that seemed to of been thrown over her. There also seemed to be things missing from the mantelpiece like a clock and a silver moneybox. The bin had been rooted through suggesting that the burglar was looking for something in particular. There where also bloody footsteps up the stairs but not back down again which suggest the murderer jumped out of an upstairs window.

We took fingerprints from the rucksack and found our murderer on the computer database. It was Colin Fisher of Barman Road who had only just got out of prison. he has been sentenced to life in prison.

Microscopes

Microscopes were invented by Anton van Leeuwenhoek. He dicovered lots of new animals and plants as well as bacteria just by looking into a micrscope. He studied blood cells and how they move and even the life cycle of insects. Because of all the wonderful work he did he was often reffered to as 'the father of microscopy'.

Microscopes are very clever. They use the same reflecting mathod as teloscopes. It's all about bending the light. In a telescope, the idea is to bend parallel light from very faraway objects into a small focus at the eye. In a microscope, the idea is to bend diverging (spreading-out) light into a parallel path, then bend that parallel-path light into a small focus at the eye. Like this.

Whats Happening?

If you want to look at something through a microscope this is what you should do.

1. First you have to mount what you want to look at on a glass slide. It's pretty easy and doesn't need explaining.
2. Light up the object. This can be done by putting a mirror underneath the object. The mirror reflects the light and sends it up the microscope giving light.
3. Then look through the eye piece lense and you can see your object clearly.

Every microscope has a diffrent zoom. It is normally written somwhere on the microscope. For example 40 means the object is 40x bigger than in real life.

Chromatography

Chromatography is widely used in forensic analysis for identification purposes. If say a lipstic stain was found on a pillow and some lipstick was taken from two suspects the chemist would want to know who's lipstick was found on the pillow. Chromatography would allow this. The chemist would dissolve a small piece of each of the two lipsticks and a sample found on the pillow. They would then use chromatography to compare each of the chromatograms. Each sample will provide a unique chromatogram (like a fingerprint). But if one was exactly the same as the chromatogram produced from the pillow stain then we have a poitive identification.

Another use would be if there had been a stalker writing disturbing letters to someone they would get some of the pen and draw on the paper and then the suspects pen would be used and they could find out who it was.

Try your own chromatography.

Chromatography is a method for analyzing complex mixtures (such as ink) by separating them into the chemicals from which they are made. Chromatography is used to separate and identify all sorts of substances in police work. Drugs from narcotics to aspirin can be identified in urine and blood samples, often with the aid of chromatography.

What you need

• Paper coffee filters• One black permanent pen• Black water soluble pens• Container full of water• Several sheets of paper• Small glasses or plastic containers• Isopropyl rubbing alcohol*• Pencils• Tape• Scissors• Stapler

Part I - Separating Black Ink

1. Cut several coffee filters into long strips, one strip per pen.

2. Fold the end of each strip over then staple it to form a loop.

3. Place a dot of ink near the bottom of each strip. Use a pencil to identify which strip belongs to which pen.

4. Poke a pencil through one of the loops you just made. Use the pencil to suspend the strip in a small glass or container.

5. Carefully add water to the glass until it reaches the bottom of the paper strip just below the ink dot. Be sure the ink stays above the water and the paper stays in the water.

6. Allow the water to soak up the strip and watch what happens to the ink drop.

7. If the ink you are testing does not spread out, re-test it using rubbing alcohol.

8. Repeat this process for each strip and compare your results.

9. Let the strips dry and tape them on a sheet of paper as a record of the different pen types.

Part 2- Secret Note Challenge

1. Turn your back while someone uses one of the pens you just tested to write a secret note on a piece of coffee filter.

2. Cut out several individual letters from the note.

3. Staple each letter to the bottom of a strip of coffee filter.

4. Conduct the chromatography experiment above to determine which pen was used to write the secret note.

Because molecules in ink and other mixtures have different characteristics (such as size and solubility), they travel at different speeds when pulled along a piece of paper by a solvent (in this case, water). For example, black ink contains several colours. When the water flows through a word written in black, the molecules of each one of the colours behave differently, resulting in a sort of “rainbow” effect. Many common inks are water soluble and spread apart into the component dyes using water as a solvent. If the ink you are testing does not spread out using water, it may be “permanent” ink. In such cases, you will have to use a different solvent such as rubbing alcohol.

DNA Fingerprinting

Like the fingerprints that came into use by detectives and police labs during the 1930s, each person has a unique DNA fingerprint. Unlike a conventional fingerprint that occurs only on the fingertips and can be altered by surgery, a DNA fingerprint is the same for every cell, tissue, and organ of a person. It cannot be altered by any known treatment. Consequently, DNA fingerprinting is rapidly becoming the primary method for identifying and distinguishing among individual human beings. An additional application of DNA fingerprint technology is the diagnosis of inherited disorders in adults, children, and unborn babies. The technology is so powerful that, for example, even the blood-stained clothing of anyone could be analyzed for evidence of a genetic disorder called Marfan's Syndrome. The characteristics of all living organisms, including humans, are essentially determined by information contained within DNA that they inherit from their parents. The molecular structure of DNA can be imagined as a zipper with each tooth represented by one of four letters (A, C, G, or T), and with opposite teeth forming one of two pairs, either A-T or G-C. The letters A, C, G, and T stand for adenine, cytosine, guanine, and thymine, the basic building blocks of DNA. The information contained in DNA is determined primarily by the sequence of letters along the zipper. For example, the sequence ACGCT represents different information than the sequence AGTCC in the same way that the word "POST" has a different meaning from "STOP" or "POTS," even though they use the same letters. The traits of a human being are the result of information contained in the DNA code. Living organisms that look different or have different characteristics also have different DNA sequences. The more varied the organisms, the more varied the DNA sequences. DNA fingerprinting is a very quick way to compare the DNA sequences of any two living organisms. DNA fingerprinting is a laboratory procedure that requires six steps:
1: Isolation of DNA.DNA must be recovered from the cells or tissues of the body. Only a small amount of tissue - like blood, hair, or skin - is needed. For example, the amount of DNA found at the root of one hair is usually sufficient.
2: Cutting, sizing, and sorting.Special enzymes called restriction enzymes are used to cut the DNA at specific places. For example, an enzyme called EcoR1, found in bacteria, will cut DNA only when the sequence GAATTC occurs. The DNA pieces are sorted according to size by a sieving technique called electrophoresis. The DNA pieces are passed through a gel made from seaweed agarose (a jelly-like product made from seaweed). This technique is the biotechnology equivalent of screening sand through progressively finer mesh screens to determine particle sizes.
3: Transfer of DNA to nylon.The distribution of DNA pieces is transferred to a nylon sheet by placing the sheet on the gel and soaking them overnight.
4-5: Probing.Adding radioactive or colored probes to the nylon sheet produces a pattern called the DNA fingerprint. Each probe typically sticks in only one or two specific places on the nylon sheet.
6: DNA fingerprint.The final DNA fingerprint is built by using several probes (5-10 or more) simultaneously. It resembles the bar codes used by grocery store scanners. Uses of DNA FingerprintsDNA fingerprints are useful in several applications of human health care research, as well as in the justice system.



Sir Alec Jeffreys is pictured here. He discovered DNA fingerprinting.

Sir Alec first made his world-changing discovery by separating strands of DNA into different sizes and showing them as bands on a photograph. What first seemed to him to be ‘a complicated mess’ has now become invaluable for police investigation, ranging from settling immigration and paternity disputes to solving rape and murder cases.

Blood Types

Blood Group Basics

There are lots of complicated diffrences beetween everyones blood types.Everyone has antigens(weird little maker things on the surface of our red blood cells. These are so tiny they can't even be seen under a microscope. Everyone has diffrent ones-only identical twins have the chance of having the same. Blood types are very importatn during blood transfusions because if you get the wrong blood it could be fatal.

The ABO System

If you have blood group A then you've got A antigens covering your red cells. Blood group B means you have B antigens, while group O has neither, and group AB has some of both. The ABO system also contains lots of little antibodies in the plasma, antibodies being the body's natural defence against foreign antigens. So blood group A has anti-B in their plasma, blood group B has anti-A . Group AB has none and group O has both of the antibodies. Which means giving someone blood from the wrong ABO group could be fatal. The anti-A antibodies in group B attack group A cells and vice versa. Which is why group A blood must never be given to a group B person. Group O negative is a different story.

The Rh System

There uis also anothre antigen. It is called the RH antigen. Some of us have it, some of us don't. If it is present, the blood is RhD positive, if not it's RhD negative. So, for example, some people in group A will have it, and will therefore be classed as A+ (or A positive). While the ones that don't, are A- (or A negative). And so it goes for groups B, AB and O. This effectively doubles the number of different blood types to be matched, because you shouldn't mix blood type A+ with blood type A-. 84% of the population is Rh positive.

Percentage of People with Diffrent Blood Types

O+ = 37%

O- = 07%

A+ = 35%

A- = 07%

B+ = 08%

B- = 02%

AB+ = 03%

AB- = 01%

O+ Group

If your blood is O Rh positive, you are especially important. Around 37% of the population share your group, but what makes you even more important is that, if necessary, your blood can be given to anyone who is Rh positive (regardless of their blood group) - and that's a staggering 83% of people.

O- Group

Because your blood group is O Rh negative, it is very special indeed. It can be given to anyone. That means your blood is the only safe option when a patient's blood group is unknown or not immediately available - such as in emergencies, or in the case of specialised procedures for unborn babies.

A+ and A- Group (its all the same info)

35% of the population have blood group A Rh positive. 7% of the population, have blood group A Rh negative. That makes a combined total of 42% of the population having blood group A. Of all the people needing blood at any given time, Group A will be needed by almost half of them.

B+ Group

Group B positive blood is extremely valuable - less than 8% of the population possess this particular group.

B- Group Fewer than two out of every hundred in the UK share this blood type.

AB+ Group

Less than 3% of the population possess this particular group.

AB- Group

Group AB negative blood is needed for the manufacture of plasma - a rich 'soup' of essential proteins - plasma is separated from red blood cells and frozen when fresh. Less than 1% of the population possess AB negative blood.